Answer:
4
Step-by-step explanation:
The factors of 84 are: 1, 2, 3, 4, 6, 7, 12, 14, 21, 28, 42, 84
The factors of 100 are: 1, 2, 4, 5, 10, 20, 25, 50, 100
They have 4 in common
100 = 2*2*5*5
84 = 2*2*3*4
the greatest common factor is a prime number whit most appearance in both numbers:
in this case the prime number is 2 and it is repeated twice in both numbers, hence 2*2 = 4
3 times
She would have to weigh the fake coins and another bag of real coins to spot a difference, and then she would need to check another bag to see which was correct. Maybe thats right.
the first one and the last one
